A section of the American River Parkway recreation trail that was closed nine months ago by a large landslide likely will not be repaired and reopened until late next spring or summer, state parks officials say.

The lengthy closure has prompted complaints from cyclists and others, but state parks officials say the situation is far from simple or safe.

Mounds of dirt and rock are lying on the trail alongside Lake Natoma in Orangevale since heavy January and February rains caused slices of the hillside to slide. Officials say the cliff above the trail is still unstable and will require stabilizing before cleanup can begin.

State parks does not have the expertise to handle the job, so it is in negotiations with Caltrans, an agency that has a lot of experience dealing with landslides and unstable slopes, according to Richard Preston, the Folsom area state parks superintendent.

The two agencies are close to signing an agreement, he said. Caltrans will assess the hillside safety. That may mean sending workers rappelling down the 70-foot cliff to get closer look, Preston said.

The state must conduct an environmental impact report, including an analysis of how the project might affect Lake Natoma.

Come winter, Caltrans crews will have to focus on highway snow and landslide removal in the mountains, meaning the main work on the local project probably will wait until spring.

Preston said the project will involve using large crowbars and inflatable air bags to pry boulders free on the embankment, knocking them down to the trail below. Once the cliff is stabilized, bulldozers can clean up the rocks and officials can assess damage to the asphalt trail.

Preston said the state has gotten calls from people unhappy that the pile of earth is still sitting there.

“Folks ask why we didn’t just go in with a bulldozer and open it up and let nature take its course. But we don’t want to put the public back at risk” with an inadequate repair, he said. “From our perspective, it’s really a safety issue. We want to make sure we do our due diligence to create a safe environment.”

Cyclists, runners and walkers, meanwhile, are using a second trail that runs on the opposite, or south, side of Lake Natoma, between Hazel Avenue and historic Folsom.